Expanding reamer



EXPANDI NG 'REAMER FiledJan. 18, 1928 I my! 121062: for. ZawardP/Eb y'mand filo/way.

.EIDWARDF. :ehmonn, or

invention.

. y, 45 1 showing the parts expanded;

Patented Apr. 15, 1930 UNITED STATES PA T, OFFICE LOS ANGEL'ES, CALIFORNIA, ASSIGINOR TO JOHN GRANT, OF LOS ANGELES, CALIFORNIA EXPANDING REAMER Application filed January 18, 1928. Serial No. 247,582.

This invention relates to improvements in V expanding drilling tools, underreamers or expansive reamers, and particularly to im-' provements in that type of reamer using sswinging expanding; cutters; the improvements being mainly in the direction of providing a reamer of that type in which the whole reamer structure is exceptionally strong and solid, particularly when expanded 10 and operating. The features of the invention, however, will be best understood from the following detailed description of a preferred and specific form of reamer in which the invention is at present embodied.

In considering the following detailed description itwill, however, be understoodthat the details of design and arrangement, except as hereinafter expressly set out in the claims, are not necessary limitations upon the of the invention is in the provision of swinging cutter carriers-carriers which swing on pivots to expand and contract'which are so I formed and inter-related that in their exg panded p'ositionsthey bear against each other scribed are not necessarily limitative of the invention expressed in the acompanying claims. I

i For the purpose of specific description of an illustrative and preferred form and adap tation of the invention, I refer to the accompanying drawings, in which Fig. 1 is a vertical central section of an expanding reamer embodying myinvention;

Fig 2 is a cross-section on line 2-2 ofFig.

Fig. 3 is a similar section showing the parts contracted;and

Fig. 4 is a cross-section on line 4-4 of Fig. 1.

. 5 y In the drawingsa suitablebody is shown For instance, one of the features vertically between the heads.

at 10, this body having an upper head 11 and a relatively reduced shank 12below the upper head, and in the particular form here illustrated the shank 12 as well as head 11 is shown as being cylindric. At the upper end of the headythe usual screw-threaded pin 13" is provided for connection with a drill stem;

and the lower end of shank 12 has a simllar screw-threaded pin 14 to which the shank of a drilling bit, or a connecting sub, 15, may

be screw-threadedly attached. Throughout the body a central circulation passage 16 extends fromend to end to feed circulating .fluidto the circulating passage or passages 15 of the drill bit below. And, in order to keep the swinging cutter carriers free, side circulation passages 16 may lead from the main passage 16 to deliver circulating fluid to the swinging carriers. I

The number of swinging carriers depends upon the number of cutters desired; in this particular instance I have chosen to illustrate three.

Thus there are three cutter carriers 20 designed, in this particular instance, to each carry a roller cutter 21 mounted on a vertical mandrel pin 22 in the cutter carrier. Each cutter carrier is recessedas illustrated at 23 to accommodate itsroller cutter, and the mandrel pins are mounted at their upper and lower ends in bores 2land 25 in. the parts of the carrier which are respectively above and below the recesses 23. I These upper and lower parts of the cutter carrier, indicated by the numerals 26 and 27 may be termed upper and lower heads, which are intercom nected by the carrier web 28 which extends The mandrel pins may be arranged to be inserted frombelow, the upper bore 24 extending only part way upwardly through the upper head'26,

but the bore 25 extending vertically clear through the lower head 27, and the mandrel pin beingsupported by a screw-threaded plug 29as illustrated in Fig. l.

Each cutter carrier has at its upper and lower ends two pivot pins 35 and 36, the two pins for each carrier being arranged on a common vertical axis in substantially the relationship to the cutter axis that is shown in Figs. 2 and 3 The upper pivot pins 35 are journalled in bores 37 in the upper body head 10; while the lower pivot pins 36 are journalled in bores 38 in a lower bearing collar 39 which fits removably upon body shank 12. Bearing collar 39 is removable from the body shank by longitudinal movement'but is rotatively fixed uponthe shank in-any suitable manner, as by a key or spline such .as illustrated .at 510 in Fig. l. The sub or drill shank 15holds bearing calla-r39 u in place and holds the whole tool'in asseln "1y;

It is preferable to provide some spr-in T means for urging the cutter carriers towar their expanded positions. Any suitable spring means may be utilized, but I have here referred to show coiled torsion springs xed in the bod at their upper ends at 46 in the upper en a of bores 37 and attached at their lower ends to spring heads 47, which heads have flat keys 48 adapted to enter slots 49 in the upper ends of pivot pins 35. These springs tend to urge the cutter carriers from thelposition of Fig. 3 to the position of Fig. 2.

:he characteristic form of the cutter carriers is shown in Figs. 2 and 3 and will now be described. The exterior surface '50 of each cutter carrier may preferably be curved and concentric with the center of the tool when the'carriers are expanded, as shown in Fig. 2. The cutter carrying end of-each carrier has a curved cylindric surface 51 concentric with the axis of its )ivot pins35 and 36. The opposite or-tail en 'the end of the swinging cutter carrier on the oppositeside of the swinging axis from the cutter carrying end-has a curved cylindric surface 52 of the same radius of curvature as surface '51 and so placed and arranged upon the carrier, that, in the expanded positions, a surface 52 at the end of one carrierbears against surface 51 at the adjacent cutter carrying end of the next carrier. It will be noted that, due to the described relationships of the swinging axes and surfaces 51 and 52, the engagement of'a surface52 with a surface 51 forms a stop to limit the outward swinging-movement of the cutter carrying end of each carrier (swinging movement of each carrier in a left-handed direction about its own pivot). Also each cutter carrier has onits inner face, and near its cylindrlc face '52, a cylindric stop face 53 which, in expanded position, bears solidly against the rbody'shank l2. 'On itsinner face 1112*1128' cutter carrying lend each carrier has acylindric face 54 which bears against body shank '12 whenxthe cutters are contracted. Theoutor faces 10*: the carriers are made up ofthe outer cyfindric surfaces hereinbefore referred to, and flat eadsurfaces "55-and 56, adiitth flat surfaces, whenthe carriers are expanded, lie in pairs ('55, 56) in common aanessueh as illustrated in Fig.2, giving a sorter-triangular cross-sectionto the composi'te bodv which is-made up cfthe three wflerearrleis whenexpanded.

The particular inter-engaging shapes of the cutter carriers may be confined to their two heads, or may extend along the whole lengths of the carriers. If the do so extend along the whole lengths of tie carriers, it- Will be seen that, in the expanded operative position, an interlocking and inter-engaging aggregate of cutter carriers is provided in such a manner that the aggre ate presents exteriorly only the vertical 'cy lindric faces 50 and the plane faces 55 and 56, without any recesses or pockets except the recesses which are occupied by roller cutters 21. This gives a smooth exterior surface not liable to catch and hold mud or other foreign matter and one which ismost easilyrota'ted with the least drag. At the same time it will be noted that the inter-engaging facesof'tlie several cutter carriers gives the carriers an exceptionally good support against the radial and circumferential thrusts to which the cutters and the carriers are subjected during active drilling. This'support of the cutters againstcircurnferential thrust and against torsions tending to swing them further outwardly, is provided not only by bearings against the body but also by bearings of the carrier ends against each other. It will be noted that, although the inter-engaging'cylindric faces 51 and 52 support eachcarrier against circumferential thrust, they-'do'not interfere at all with collapsing action of the cutters, due to the fact that they are concentric about 'the corresponding pivotal axes.

I claim:

1. In an expanding reamer or the like, a plurality of swinging cuttercarriersmounted to swing on longitudinal axes which are spaced around a central axis of the body, eachcarrier having a cutter carrying end to one side of its swinging axis and having a tail end'extending to the other side of its swinging axis, and each carrier having at its cutter-carrying end a surface engageable by the tail end of an'adja'cent carrier.

2. In an expanding reamer or the like, a plurality of swinging cutter carriers mounted to swing on longitudinal axes which "are spaced. around a central axis of the body,

each carrier having a cutter carrying end' to one side of its swinging axis and having a tail end extending to the other side'of its swinging axis, and each carrier having at its cutter-carrying end a surface engageable by the tail end of an adjacent carrier, theintei engaging surfaces of the head and tail ends of any two adjacent carriers being, when the cutter carrying ends are swung outwardly, substantially concentric about the swinging axis of the carrier whose-cutter carrying end surface J's-being engaged.

3. In an expanding reamer or the like, a plurality-of swinging cutter carriers mounted toswing on longitudinal axes which are spaced around a central axis or the "body,

cutter-carrying end a surface engageable by i each carrier having a cutter carrying end to one side of its swinging axis and having a tail end extending to the other side of its swinging axis, and each carrier having at its cutter-carrying end a surface engageable by the tail end of an adjacent carrier, each carrier also having an inner surface engageable with the body when the cutter carrying ends of the carriers are swung outwardly.

4. In an expanding reamer or the like, a plurahty of swinging cutter carrlers mounted to swing on longitudlnal axes which are spaced around a central axis of the body,

each carrier having a cutter carrying end to one side of its swinging axis and having a tail end extending to the other side'of its swinging axis, and each carrier having at its the tail end of an adjacent carrier, the interengaging surfaces of the head and tail ends carriers mounted to swing on longitudinal axes which are arranged about a central axis of the body, a cutter carried at one end of each carrier to one side of its swinging axis, and each carrier having a tail end projecting to the other side of its swinging axis, and the cutters being so formed that, when their cutter carrying ends are swung out-- wardly they engage the cutter carrying end of one with the tail end of another.

v6. In an expanding reamer or the like, the combination of a body, a plurality ofcutter carriers mounted to swing on longitudinal axes which are arranged about a central axis of the body, a cuttercarried at one end of each carrier to one side of its swingin axis, and each carrier having a tail end pro ecting to the other side of its swinging axis, and the cutters being so formed that when their cutter carrying ends are swung outwardly they engage the cutter carrying end of one with the tail end of another, and each cutter carrier having an engagement surface which bears against the body when the cutter carrying ends of the carriers are swung outwardly.

7 In an expansive reamer or the like, the combination of a central body, swinging cutter carriers mounted on longitudinal axes spaced around the central axis of the body, the carriers each having cutter carrying ends to one side of their respective axes and having swinging tail ends to the other side of their said axes, and the several carriers interengaging when thelr cutter carrying ends are swungoutwardly to present an exterior aggregate surface unbroken by recesses.

In witness that I claim the foregoing I have hereunto subscribed my name this 20th day of December, 1927.

EDWARD F. RAYMOND. 

